Sandra Bullock’s career of romantic comedies and thrillers has always been a predictably undulating sine wave of hot and cold streaks: The highs of Speed and While You Were Sleeping led to the trough of Two If by Sea and Speed 2… then back up to Hope Floats, etc. Though every few years she would try out a “serious” movie (In Love and War, Infamous), she’d quickly veer back to flexing her most powerful three muscles: kissing and snorting, being a klutz, or shooting someone while kissing and snorting and/or being a klutz. But this year, at the age of 45 (when a lot of actresses find the spectrum of roles available to them narrowing), she was not only Hollywood’s top moneymaker, notching two blockbusters with The Proposal and The Blind Side, but she’s being discussed as a serious contender for a Best Actress Oscar. Try it out: “Here comes Academy Award Winner Sandra Bullock!” Wow, that feels weird. But how she pulled it off could serve as a primer to any popular comic actor or actress who wants to make the leap to the Kodak Theater.

What’s particularly impressive about all this Oscar buzz around Bullock is that she managed to do it without radically reinventing herself. The Blind Side’s Leigh Anne Tuohy may be a real person, but she’s not the kind of historical or ripped-from-the-headlines figure that usually attracts awards: She’s not Edith Piaf, Queen Elizabeth II, or Virginia Woolf. After misfires like In Love and War, Bullock learned that maybe she wasn’t cut out to play these kinds of parts. So, in The Blind Side, she takes a character who displays some of the all-American spunk and energy of her own onscreen persona and gives it a more serious twist. She doesn’t try to “lose herself” in the part; moviegoers can recognize the Sandra Bullock they know and love in Leigh Anne. It’s a lesson some other comic actors (coughJimCarreycough) have tried to ignore.

At the same time, while these are strong, plucky characters, they’re not exactly the America’s Sweetheart image of Bullock’s younger years. The Proposal plays like a romantic-comedy variation on The Devil Wears Prada, and her character in The Blind Side is a take-charge, suburban Christian spitfire. (The specter of Sarah Palin looms large over both films; The Proposal is all about the superior down-home values of Ryan Reynolds’s Alaska family.) Bullock did the right thing by taking on these somewhat more abrasive characters. Of course, it could also be argued that the most abrasive character she played this year was in the horrendous dud All About Steve — whose foul taste an Oscar win will also help to clear. Almost.